The present invention relates to a high response speed liquid crystal display having a wide viewing angle.
One known type of liquid crystal displays which have been put to practical use is Twisted Nematic (TN) Mode liquid crystal displays using a nematic liquid crystal. This mode, however, has drawbacks such as low response speed and narrow viewing angles. Ferroelectric Liquid Crystals (FLC) are known as a display mode having high response speed and wide viewing angles but suffer from serious problems in shock resistance and temperature characteristics. The Polymer Dispersed Liquid Crystal Mode, which makes use of light scattering, is a rubbingless alignment display mode, yet it still needs improvements in viewing angles and its response is not fast enough.
To overcome their drawbacks, there has been proposed the Optically Compensated Bend (OCB) Mode as a display mode having fast response and wide viewing angles (Japanese Patent Publication (KOKAI) No. 7-84254 (1995)).
FIG. 21 shows a conceptual structural sectional view of the pixel region of an OCB mode liquid crystal display.
As shown in FIG. 21, this liquid crystal display of the OCB mode has alignment layers 19 which are oriented in a certain direction; a liquid crystal cell 14 in which a bend alignment or a bend alignment including a twisted alignment is generated at the center of the cell 14 by voltage application; and a phase compensator 3 for optical phase compensation for achieving low voltage actuation and enlarged viewing angles. Regarding performance, the OCB mode can provide an active matrix type liquid crystal display having a wide viewing angle and high response speed. In addition, it has the high potential of finding wide applications as a transmissive or reflective type liquid crystal display.
The above liquid crystal display is formed as follows. The alignment layers 19 are attached to the inner surface of an array substrate 6 on which switching elements 13 or the like each connected to an pixel electrode 18 for actuating a pixel region is placed and to the inner surface of an opposed substrate 5 having an opposed electrode 17 thereon. These alignment layers 19 have undergone alignment treatment so as to be parallel to each other and have pretilt angles which are about several to ten degrees, being opposite to each other in a positive/negative sense. A nematic liquid crystal having positive dielectric anisotropy is inserted between the alignment layers 19 to form a liquid crystal layer 12. Accordingly, there is formed a spray alignment 11 composed of an alignment region in which liquid crystal molecules are diagonally spread in a vertically symmetrical manner when no voltage is applied.
Then, a voltage higher than the critical transition voltage is applied across the above electrodes, whereby transition is caused to form the bend alignment 13 composed of an alignment region in which the liquid crystal molecules at the center are raised upright or the liquid crystal molecules including twisted alignment are raised in a twisted manner, as shown in FIG. 21(b) and this region is extended.
At least one polarizer and at least one phase compensator are disposed on the outer sides of the upper and lower substrates, extending in a specified axial direction. Specifically, there are provided polarizers 1, 2 and the phase compensator 3 for optically compensating for the bend alignment cell and lowering voltage in order to attain sufficient contrast and an increased view angle.
After the transition of the whole pixels, driving signal voltage is varied to change the degree of the bend alignment state of the liquid crystal molecules, thereby changing the phase difference to be utilized for motion display. Therefore, in the liquid crystal display of the OCB mode, it is necessary to develop transition cores for transition from the spray alignment to the bend alignment to bring the pixels into an uniform bend alignment state and to cause such transition throughout the TFT panel pixel region without fail. In reality, it is not easy to develop transition cores without fail.
When observing the above pixel region with a microscope, it has been found that transition cores develop around spacers which are provided so as to scatter for gap formation or that transition cores develop around source lines and gate lines wired along the pixel electrodes, but developing positions are not fixed. In some cases, transition cores are not developed at all. In this case, the resultant panel has alignment defects and visible defects.
As an attempt to promote the above transition, there has been proposed a method in which a voltage higher than the critical transition voltage is applied across the opposed electrode and pixel electrodes of the liquid crystal cell. However, the applied voltage and the time required for voltage application, which are necessary for the transition, vary considerably depending on liquid crystal materials. With some liquid crystal materials, a time ranging from tens of seconds to several minutes is required for applying about 20V across the facing electrodes in order to cause a transition in a TFT liquid crystal panel of the OCB mode. This case is not practical not only in view of the wait time taken for starting displaying but also in view of the power consumption of the liquid crystal display and the reliability of the driving unit.
In such circumstances, there have been strong demands to a technique for enabling a reliable transition of alignment within all of hundreds of thousands of pixels in the display panel of an OCB mode liquid crystal display.
A series of inventions has been made taking the present status of the technology described above into account. The prime object of the inventions is therefore to provide a liquid crystal display which has no display defects and high response speed and is therefore suitable for displaying moving pictures and which also has a wide viewing angle, since it can cause alignment transition with substantial reliability and complete it in an extremely short time. More particularly, the object of the inventions is to provide a bend alignment type liquid crystal display which has high response speed and is therefore suitable for displaying moving pictures, since it can cause bend alignment transition with substantial reliability and complete it in an extremely short time.
The series of inventions is based on the same or similar concepts, but embodied by different examples. In the present specification, these inventions are classified according to analogy into a first invention group, a second invention group, a third invention group, a fourth invention group and a fifth invention group. The contents of each group (i.e., each invention group) will be hereinafter described in order.
(1) First Invention Group
The first invention group is associated with a liquid crystal display wherein where the alignment state of a liquid crystal to which no voltage is applied is defined as an alignment state 1 and the alignment state of the liquid crystal used for performing displaying is defined as an alignment state 2, the alignment state 1 differs from the alignment state 2; and wherein for easy, reliable transition from the alignment state 1 to the alignment state 2, the unevenness of a surface of a substrate is flattened and an interface of a liquid crystal layer is flattened.
In liquid crystal displays having a conventional active matrix substrate, significant irregularities are usually present on the substrates. This is due to the process in which the top layer, that is, an insulating layer having the greatest level difference is removed to expose the pixel electrodes. Level differences are also caused by source wiring and gate wiring positioned around the pixels. Thus, the presence of level differences is usual for active matrix substrates.
In conventionally used TN type liquid crystal displays, the presence of level differences causes alignment disturbance at their positions, resulting in light leakage. To solve this problem, it is necessary to seal the regions where light leakage occurs with a black matrix, which however causes the problem of decreasing brightness. As an attempt to overcome the alignment disturbance and light leakage, there has been proposed one technique according to which a resin layer is formed on the substrate having irregularities thereon and pixel electrodes are then formed on the resin layer to flatten the device.
In liquid crystal displays in which the alignment state when no voltage is applied differs from the alignment state when displaying can be performed (e.g., OCB mode liquid crystal displays), xe2x80x9ctransitionxe2x80x9d operation is necessary for shifting to the alignment state for displaying.
Since OCB mode liquid crystal displays have a parallel alignment different from that of TN type liquid crystal displays, they do not suffer from the problem of alignment disturbance such as seen in TN type liquid crystal displays. However, the inventors have newly found that level differences adversely affect the transition.
In OCB mode liquid crystal displays, transition is carried out by applying transition voltage. At that time, the bend alignment develops from transition cores and this alignment state is expanding. It has, however, been found that the development of the bend alignment ceases when it has reached an irregular region in the substrate and particularly a region where the substrate is raised and therefore the liquid crystal layer becomes thin. The bend alignment usually develops along a defect. In a region where the liquid crystal layer is thin, the defect is intermittent and therefore the development stops. In many cases, such a defect is found in a boundary between two types of spray alignment states which differ from each other in the tilting direction of the liquid crystal molecules tilted with respect to the direction of cell thickness.
The inventors have also found that when transition is not completed with a voltage having a specified transition waveform, leaving some pixels in the spray alignment state, a transition to the bend alignment gradually occurs due to normal display driving operation which is performed later.
Based on the above findings, the inventors have accomplished a liquid crystal display such as OCB mode liquid crystal displays wherein where the alignment state of a liquid crystal to which no voltage is applied is defined as an alignment state 1 and the alignment state of the liquid crystal used for performing displaying is defined as an alignment state 2, the alignment state 1 differs from the alignment state 2; and wherein for easy, reliable transition, the unevenness of a surface of a substrate is flattened and an interface of a liquid crystal layer is flattened.
More specifically, a first aspect of the invention is a liquid crystal display having a pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, wherein where the alignment state of a liquid crystal when no voltage is applied to the liquid crystal layer is defined as an alignment state 1 and the alignment state of the liquid crystal used for performing displaying is defined as an alignment state 2, the alignment state 1 differs from the alignment state 2; and wherein the interface between the liquid crystal layer and at least either one of the pair of substrates is flattened.
With the above arrangement, irregularities in the interface between the liquid crystal layer and the substrate can be reduced so that the transition from the alignment state 1 to the alignment state 2 can be easily and reliably carried out.
A second aspect of the invention is a liquid crystal display constructed according to the first aspect of the invention, in which either of the above pair of substrates is an active matrix substrate. According to the above arrangement, although the active matrix substrate has source wiring, gate wiring and the like formed around the pixels and therefore has great level differences, such a substrate is flattened to have a flat configuration so that the transition from the alignment state 1 to the alignment state 2 can be easily and reliably carried out.
A third aspect of the invention is a liquid crystal display constructed according to the first aspect of the invention, wherein the interface is flattened by a flattening film composed of a resin layer.
A fourth aspect of the invention is a liquid crystal display constructed according to the third aspect of the invention, wherein electrodes are formed on at least part of the flattening film.
A fifth aspect of the invention is a liquid crystal display constructed according to the first aspect of the invention, wherein the alignment state 1 is a spray alignment state and the alignment state 2 is a bend alignment state.
The above arrangements make it possible to provide OCB mode liquid crystal displays in which easy and reliable transition is enabled.
A sixth aspect of the invention is a liquid crystal display constructed according to the first aspect of the invention, wherein the level differences of irregularities on the substrates are 1 xcexcm or less.
A seventh aspect of the invention is a liquid crystal display constructed according to the first aspect of the invention, wherein the level differences of irregularities on the substrates are 0.5 xcexcm or less.
By limiting the level differences of the irregularities on the substrates to 1 xcexcm or less or more preferably to 0.5 xcexcm or less, the transition from the alignment state 1 to the alignment state 2 can be easily, reliably performed.
An eighth aspect of the invention is a liquid crystal display constructed according to the second aspect of the invention, wherein the active matrix substrate has a plurality of pixel electrodes and the spacing between the pixel electrodes is within the range of from 1 xcexcm to 10 xcexcm.
A ninth aspect of the invention is a liquid crystal display constructed according to the second aspect of the invention, wherein the active matrix substrate has a plurality of pixel electrodes and the spacing between the pixel electrodes is within the range of from 1 xcexcm to 5 xcexcm.
As described above, the preferred spacing between the pixel electrodes is within the range of from 1 xcexcm to 10 xcexcm or, more preferably, within the range of from 1 xcexcm to 5 xcexcm, which makes it easy to reliably carry out the transition from the alignment state 1 to the alignment state 2.
A tenth aspect of the invention is a liquid crystal display constructed according to the eighth aspect of the invention, wherein at least part of the pixel electrodes is higher than the average height of the pixel electrodes. The higher part of the pixel electrodes facilitates the development of transition cores.
An 11th aspect of the invention is a liquid crystal display constructed according to the eighth aspect of the invention, wherein a voltage is applied across the pixel electrodes and an opposed electrode formed on the other one of the pair of substrates, thereby transiting the alignment state of the liquid crystal layer to a bend alignment to perform displaying in the condition after the transition.
(2) Second Invention Group
A 12th aspect of the invention is an active matrix type liquid crystal display wherein a liquid crystal layer is sandwiched between an array substrate having pixel electrodes and an opposed substrate having an opposed electrode and the liquid crystal layer is oriented in a bend alignment thereby performing displaying, and wherein conductive formation members, which are electrically conducted to the opposed electrode but electrically insulated from the array substrate, are formed on the opposed substrate.
A 13th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the conductive formation members are placed in the space between every adjacent pixel electrodes so as to be electrically insulated from the array substrate.
With the above arrangements, a diagonal strong electric field is developed and applied across the conductive formation members and the pixel electrodes, causing electric field distortion which brings the liquid crystal molecules in the liquid crystal layer positioned in the vicinity of the conductive formation members and in the vicinity of the pixel electrodes into a b-sprayed alignment state so that the energy of the distortion of the liquid crystal molecules becomes greater than that of their surroundings. In this condition, a high voltage is applied across the pixel electrodes and the opposed electrode thereby further providing energy so that transition cores of the bend alignment can be developed and the region of the bend alignment can be extended.
A 14th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the pixel electrodes are positioned on a flattening film formed on the array substrate.
This arrangement further makes it possible to easily and reliably carry out the transition from the spray alignment to the bend alignment.
A 15th aspect of the invention is a liquid crystal display constructed according to the 14th aspect of the invention, wherein the level differences of irregularities on the flattening film are 1 xcexcm or less.
A 16th aspect of the invention is a liquid crystal display constructed according to the 14th aspect of the invention, wherein the level differences of irregularities on the flattening film are 0.5 xcexcm or less.
By imposing such level difference limitation that the level differences of irregularities on the substrate are 1 xcexcg m or less or more preferably 0.5 xcexcm or less, the transition from the spray alignment state to the bend alignment state can be easily, reliably performed.
A 17th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the array substrate has a plurality of pixel electrodes and the spacing between the pixel electrodes is within the range of from 1 xcexcm to 10 xcexcm.
An 18th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the array substrate has a plurality of pixel electrodes and the spacing between the pixel electrodes is within the range of from 1 xcexcm to 5 xcexcm.
By limiting the spacing between the pixel electrodes to 1 xcexcm to 10 xcexcm or more preferably 1 xcexcm to 5 xcexcm, the transition from the spray alignment to the bend alignment can be developed in a better condition.
A 19th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the conductive formation members are covered with an insulating material.
With the above arrangement, the pixel electrodes and the opposed electrode are electrically insulated from each other since the conductive formation members have an electric insulation relationship with the array substrate, so that a liquid crystal display having excellent performance can be attained.
A 20th aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the height of the conductive formation members is smaller than the gap between the array substrate and the opposed substrate.
A 21st aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein the conductive formation members are spacers for maintaining the gap between the array substrate and the opposed substrate to be constant.
The above arrangements actualize a spacer-less process which does not need provision of ordinary spacers so that the manufacturing process can be simplified. Further, the arrangements make it possible to achieve uniform displaying so that a liquid crystal display excellent in displaying performance can be obtained.
A 22nd aspect of the invention is a liquid crystal display constructed according to the 12th aspect of the invention, wherein a voltage is applied across the pixel electrodes and the opposed electrode to transit the alignment state of the liquid crystal layer to the bend alignment to perform displaying in the condition after the transition.
(3) Third Invention Group
A 23rd aspect of the invention is a liquid crystal display which comprises a pair of substrates having electrodes and a liquid crystal layer sandwiched between the pair of substrates; wherein liquid crystal molecules in the liquid crystal layer are oriented in a bend alignment to perform displaying; and wherein at least one conductive particle having a diameter smaller than the gap between the pair of substrates is placed on the electrode surface of at least either one of the substrates.
A 24th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein the conductive particle is placed on the electrode surface of at least either one of the substrates so as to be positioned under an alignment layer.
A 25th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein the conductive particle is placed on the electrode surface of at least either one of the substrates so as to be mixed with and dispersed in an alignment layer.
With the above arrangements, electrical field concentration occurring in the conductive particle causes a change in alignment in the neighborhood of the conductive particle, creating a transition core for a bend alignment with the conductive particle serving as a base point, and the bend alignment region is expanded by high voltage being continuously applied. Thus, the transition can be reliably and readily carried out to obtain an OCB display mode liquid crystal display composed of a liquid crystal cell free from display defects and having high response speed, a wide viewing angle and high picture quality.
A 26th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein one of the pair of substrates has a pixel electrode and a switching element for every pixel.
A 27th aspect of the invention is a liquid crystal display constructed according to the 26th aspect of the invention, wherein the pixel electrodes are formed on a flattening film for covering the switching elements or wiring electrodes flat.
This arrangement further facilitates the transition to the bend alignment.
A 28th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein a voltage is applied across the electrodes to transit the alignment state of the liquid crystal layer to the bend alignment to perform displaying in the condition after the transition.
A 29th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein the conductive particle is a resin particle or an inorganic material particle the surface of which is coated with a conductive thin film.
A 30th aspect of the invention is a liquid crystal display constructed according to the 23rd aspect of the invention, wherein the diameter of the conductive particle is within the range of from one hundredth the gap between the substrates to one half the gap between the substrates.
The reason why such a limitation is imposed is that if the diameter of the conductive particle is smaller than one hundredth the substrate gap, the transition promoting effect decreases and if the diameter of the conductive particle is larger than one half the substrate gap, the pair of substrates are likely to electrically contact with each other.
A 31st aspect of the invention is a method of producing a liquid crystal display which comprises a pair of substrates having electrodes and a liquid crystal layer sandwiched between the pair of substrates and wherein displaying is performed by orienting liquid crystal molecules within the liquid crystal layer in a bend alignment, the method comprising:
a dispersion step of dispersedly securing a conductive particle having a diameter smaller than the gap between the substrates to the electrode surface of at least either one of the substrates; and
an alignment layer formation step of forming an alignment layer by applying an alignment film material to the electrodes and baking it.
A 32nd aspect of the invention is a method of manufacturing a liquid crystal display which has a pair of substrates having electrodes and a liquid crystal layer sandwiched between the pair of substrates and wherein displaying is performed by orienting liquid crystal molecules within the liquid crystal layer in a bend alignment, the method comprising an alignment layer formation step of disposing a conductive particle in a mixed and dispersed manner by applying a material to the electrode surface of at least one of the substrates and baking it, the material containing the conductive particle which has a diameter smaller than the gap between the substrates and is mixed with and dispersed in the alignment film material.
These methods obviate the need for a photolitho-process for forming projections, thereby simplifying the manufacturing method and reducing manufacturing cost. Further, these methods make it possible to reliably, quickly cause a transition and to obtain an OCB display mode liquid crystal display composed of a liquid crystal cell free from display defects and having high response speed, a wide viewing angle and high picture quality.
(4) Fourth Invention Group
A 33rd aspect of the invention is a liquid crystal display which has a pair of substrates including electrodes and a liquid crystal layer sandwiched between the pair of substrates; wherein the liquid crystal layer is oriented in a spray alignment; and wherein the surfaces of alignment layers formed on the surfaces of the electrodes each have an irregular configuration.
A 34th aspect of the invention is a liquid crystal display constructed according to the 33rd aspect of the invention, wherein the irregular configuration is a configuration formed by regions changing in thickness in the alignment layers.
A 35th aspect of the invention is a liquid crystal display constructed according to the 33rd aspect of the invention, wherein the alignment layers are formed by letterpress printing.
With the above arrangements, the pretilt angle of liquid crystal molecules within the liquid crystal layer becomes spuriously increased owing to the alignment layer regions different in thickness, so that a shift to the bend alignment can be quickly carried out during an initialization process for a spray to bend transition.
A 36th aspect of the invention is a liquid crystal display constructed according to the 33rd aspect of the invention, wherein either one of the pair of substrates is an array substrate having pixel electrodes formed thereon, a flattening film is formed on the array substrate, and the flattening film has an irregular configuration.
By virtue of the above arrangement, the liquid crystal molecules within the liquid crystal layer are brought into an alignment state in which the liquid crystal molecules have various pretilt angles with respect to the surface of the alignment layer which has an irregular configuration resulting from the provision of the irregular flattening film, so that a quick transition to the bend alignment can be performed during an initialization process for a spray to bend transition.
A 37th aspect of the invention is a liquid crystal display constructed according to the 33rd aspect of the invention, wherein either of the substrates is a reflective substrate and the reflecting surface of this substrate has an irregular configuration.
By virtue of the above arrangement, the liquid crystal molecules within the liquid crystal layer are brought into an alignment state in which the liquid crystal molecules have various pretilt angles with respect to the surface of the alignment layer which has an irregular configuration resulting from the provision of the irregular reflective film, so that a quick transition to the bend alignment can be performed during an initialization process for a spray to bend transition.
A 38th aspect of the invention is a liquid crystal display constructed according to the 33rd aspect of the invention, wherein a voltage is applied across the electrodes to transit the alignment of the liquid crystal layer to a bend alignment to perform displaying in the condition after the transition.
A 39th aspect of the invention is a method of manufacturing a liquid crystal display which comprise a pair of substrates having electrodes and a liquid crystal layer sandwiched between the pair of substrates; wherein the liquid crystal layer is oriented in a spray alignment; and wherein the surfaces of alignment layers formed on the surfaces of the electrodes each have an irregular configuration,
the method comprising the step of forming the irregular configurations of the electrode surfaces by use of a UV asher, ozone asher, UV/ozone asher or the like.
A 40th aspect of the invention is a method of manufacturing a liquid crystal display which has a pair of substrates having electrodes and a liquid crystal layer sandwiched between the pair of substrates; wherein the liquid crystal layer is oriented in a spray alignment; and wherein the surfaces of alignment layers formed on the surfaces of the electrodes each have an irregular configuration, the method comprising: a dispersion step of dispersing, beforehand, powder or minute particles into printing varnish used for forming the alignment layers on the surfaces of the electrodes; and an alignment layer formation step of forming the alignment layers by applying the varnish onto the surfaces of the electrodes and baking the varnish.
These methods obviate the need for a photolitho-process for forming projections, thereby simplifying the manufacturing method and reducing manufacturing cost. In addition, the liquid crystal molecules within the liquid crystal layer are consequently brought into an alignment state having various liquid crystal directors, but they are basically in a state having surface alignment directors perpendicular to the substrates. As a result, a liquid crystal display can be obtained in which a shift to the bend alignment can be quickly performed with the portions having directors perpendicular to the substrates as cores, during an initialization process for a spray to bend transition.
(5) Fifth Invention Group
A 41st aspect of the invention is a liquid crystal display which comprises a pair of substrates having electrodes and a spray-aligned liquid crystal layer sandwiched between the pair of substrates; wherein a plurality of spacers are placed between the pair of substrates; wherein the spacers are securely attached to at least either one of the substrates with an adhesive which increases the pretilt angle of liquid crystal molecules within the liquid crystal layer; and wherein the adhesive is spread over the substrate.
A 42nd aspect of the invention is a liquid crystal display constructed according to the 41st aspect of the invention, wherein the adhesive is spread over a distance approximately no less than the diameter of each spacer, being centered on the spacer.
A 43rd aspect of the invention is a liquid crystal display constructed according to the 41st aspect of the invention, wherein the adhesive is spread, in one direction from each spacer, over a distance approximately no less than the radius of the spacer, being centered on the spacer.
With the above arrangements, the liquid crystal molecules located at each spacer are oriented in a one-side HAN alignment or HAN alignment, the one-side HAN alignment being such that the pretilt angle is spuriously increased by regions where said at least one of the pair of substrates differ from the other substrate. Therefore, a shift to the bend alignment can be quickly performed during an initialization process for a spray to bend transition.
A 44th aspect of the invention is a liquid crystal display constructed according to the 41st aspect of the invention, wherein the adhesive contains, as a component, a fluorine type alignment material, a fluorine type material or a long-chain alkyl material.
A 45th aspect of the invention is a liquid crystal display constructed according to the 41st aspect of the invention, wherein a voltage is applied across the electrodes to cause a transition of the liquid crystal layer from a spray alignment to a bend alignment, thereby performing displaying.
A 46th aspect of the invention is a method of manufacturing a liquid crystal display which comprises a pair of substrates having electrodes and a spray-aligned liquid crystal layer sandwiched between the pair of substrates, the method comprising: a spacer scattering step of scattering spacers onto at least either one of the pair of substrates, the spacers having an adhesive adhered thereto which increases the pretilt angle of liquid crystal molecules within the liquid crystal layer; a substrate stationary placement step of placing the substrate so as to be stationary over which the adhesive is allowed to spread; and a liquid crystal cell formation step of forming a liquid crystal cell by sticking the pair of substrates together.
A 47th aspect of the invention is a liquid crystal display manufacturing method according to the 46th aspect of the invention, wherein in the substrate stationary placement step, the substrate is horizontally placed so as to be stationary and the adhesive is spread over a distance approximately no less than the diameter of each spacer, being centered on the spacer.
A 48th aspect of the invention is a liquid crystal display manufacturing method according to the 46th aspect of the invention, wherein, in the substrate stationary placement step, the substrate is vertically placed so as to be stationary and the adhesive is spread, in one direction from each spacer, over a distance approximately no less than the radius of the spacer, being centered on the spacer.
With the above methods, the liquid crystal molecules located at each spacer are oriented in a one-side HAN alignment in which the pretilt angle is spuriously increased by regions in at least one of the pair of substrates which differ from their corresponding regions in the other substrate. This enables an OCB type liquid crystal display in which a shift to the bend alignment can be quickly performed during an initialization process for a spray to bend transition.
A 49th aspect of the invention is a method of manufacturing a liquid crystal display which comprises a pair of substrates having electrodes and a spray-aligned liquid crystal layer sandwiched between the pair of substrates, the method comprising: a spacer scattering step of scattering spacers onto at least either one of the pair of substrates, the spacers having an adhesive adhered thereto which increases the pretilt angle of liquid crystal molecules within the liquid crystal layer; and a substrate stationary placement step of sticking the pair of substrates together on which the adhesive is allowed to spread.
With the above method, the liquid crystal molecules located at each spacer are oriented in a HAN alignment in which the pretilt angle is spuriously increased, so that an OCB type liquid crystal display can be obtained in which a shift to the bend alignment is quickly performed during an initialization process for a spray to bend transition.